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991.
通过在石墨烯中引入内消旋-2,3-二巯基琥珀酸(DMSA)构建三维立体结构,原位合成了CdS@DMSA-GO复合材料。实验表明,反应温度对所得材料的结构和性能具有重要的影响。CdS@DMSA-GO-100℃对罗丹明B和刚果红具有最佳的吸附和光催化降解性能,降解效率可达96%以上。自由基捕获实验表明,·O2在催化过程中是主要的活性氧物质。  相似文献   
992.
Lightweight structural materials are important for the energy efficiency of applications, particularly those in the building sector. Here, inspired by nature, we developed a strong, superhydrophobic, yet lightweight material by simple in situ growth of nano‐SiO2 and subsequent densification of the wood substrate. In situ generation of SiO2 nanoparticles both inside the wood channels and on the wood surfaces gives the material superhydrophobicity, with static and dynamic contact angles of 159.4o and 3o, respectively. Densification of the wood to remove most of the spaces among the lumen and cell walls results in a laminated, dense structure, with aligned cellulose nanofibers, which in turn contributes to a high mechanical strength up to 384.2 MPa (7‐times higher than natural wood). Such treatment enables the strong and superhydrophobic wood (SH‐Wood) to be stable and have excellent water, acid, and alkaline resistance. The high mechanical strength of SH‐Wood combined with its excellent structural stability in harsh environments, as well its low density, positions the strong and superhydrophobic wood as a promising candidate for strong, lightweight, and durable structural materials that could potentially replace steel.  相似文献   
993.
Two A-B-C type conjugated amphiphilic triblock fullerene derivatives C60-2 HMTPB and C60-2 EHTPB were obtained in multi steps synthesis with three different blocks,and the amphiphilic diblock molecular C60-4 TPB was also preferred as a reference.When as modifying layer on zinc oxide(ZnO),the three fullerene derivatives can all reduce the work function of ZnO via modulation of the interfacial dipoles and lead a better electrical coupling.As introducing treatment of toluene,the obvious self-assembly of fullerene derivatives were observed,which were supported by X-ray diffraction and contact angle of water measurement.Base on PTB7-Th:PC71 BM system,the inverted organic solar cells devices with structure of ITO/ZnO/fullerene derivatives/PTB7-Th:PC71BM/Mo03/Al got power conversion efficiencies of 8.62%,8.83%and 9.00%for C60-4 TPB,C60-2 HMTPB and C60-2 EHTPB,respectively,compared 8.13%of devices with bare ZnO.The result of conjugated amphiphilic triblock fullerene derivatives provides a straightforward approaching by simultaneously modulating the morphology and interfacial work function of ZnO,which can also lead high performance in optoelectronic devices.  相似文献   
994.
Carbon dots(CDs) with multi-color emissive properties and a high photoluminescent quantum yield(PLQY) have attracted great attention recently due to their potential applications in chemical,environmental,biological and photo-electronic fields.Solvent-dependent effect in photoluminescence provides a facial and effective approach to tune the emission of CDs.In this study,green emissive nitrogen-doped carbon dots(N-CDs) are synthesized from p-hydroquinone and ethylenediamine through a simple hydrothermal method.The as-prepared N-CDs possess a robust excitation-independent green luminescence and a high PLQY of up to 15.9%.Further spectroscopic characterization indicates that the high PLQY is achieved by the balance of nitrogen doping states and the surface passivation extent in CDs.The N-CDs also exhibit solvent-dependent multi-color emissive property and distinct PLQY in different solvents(the maximum can reach up to 25.3%).Furthermore,the as-prepared N-CDs are applied as fluorescence probes to detect acetone and H2O2 in water.This method has exhibited a low detection limit of acetone(less than 0.1 %) and a quick and linear response to the H_2O_2 with the concentration from 0 to 120 μmol/L.This work broadens the knowledge of applying CDs as probes in the bio and chemical sensing fields.  相似文献   
995.
Here we described the design and synthesis of a discrete 3D amphiphilic metallacage 4,in which the tetragonal prismatic frameworks act as the hydrophobic cores and the poly(ethylene glycol)(PEG)chains as the hydrophilic tails.The structure of 4 was characterized by 1H NMR,31P NMR and electrospray ionization time-of-flight mass spectrometry(ESI-TOF-MS).Notably,4 with its Iong PEG tails was subsequently ordered into micelles at a low concentration(1.20×10^-6 mol/L)in water.As the concentration and cultivation time increased,the micelles can further self-assembly into nanofibers and nanoribbons.Considering the dynamic property of the coordination bond,these structures show reversible transformation under external stimuli.  相似文献   
996.
介绍了以2-碘苯胺和苯硼酸为原料,通过Suzuki偶联反应、重氮化反应、氧化反应等3步合成环状二苯基碘盐,并进一步应用于二苯并噻吩的合成。本实验涉及有机化合物的合成、结构表征以及应用,将有机化学基础理论知识、基本实验技能与学科研究热点相结合,能够有效培养学生的科学研究素养。该实验牵涉到气相质谱、核磁及熔点仪等仪器的使用,锻炼学生动手操作仪器的能力及综合实验技能,适合作为高年级学生的综合实验。  相似文献   
997.
“本博学位论文连做”培养模式是学士论文阶段在夯实理论基础的同时,改变本科阶段以学习课程为主的思维模式为以创新研究为主的思维模式;短暂的硕士阶段在理论知识进一步升华的基础上掌握本学科的研究现状和发展方向,提升发现问题、分析问题和解决问题的能力;博士阶段瞄准学科前沿,启发其发掘“新方法”和“新思路”,有效地实现学士学位论文和博士学位论文连做。  相似文献   
998.
为提高石墨相氮化碳(g-C3N4)对可见光的利用率及光催化效率,采用热聚合与直接负载等方法,将g-C3N4负载于蒙脱石表面,制备了g-C3N4/蒙脱石复合光催化材料,其结构经SEM, FT-IR及XRD表征。以罗丹明B(RhB)为目标污染物,研究了不同负载量g-C3N4/蒙脱石复合光催化剂的可见光催化性能。并分别以对苯醌、碘化钾和异丙醇为自由基捕获剂,研究了复合材料的光催化机理。结果表明:当g-C3N4的质量分数为83%(CN/M-83%)时,RhB经可见光照射1 h后,降解率达到99.2%。光催化速率常数为纯g-C3N4光催化速率常数的3.2倍。  相似文献   
999.
质子交换膜(PEM)是质子交换膜燃料电池的核心组件之一,具有隔绝阴阳极、提供质子传递通道和阻止燃料渗透的作用. 商业化应用的全氟磺酸PEM存在燃料渗透严重、高温条件下导电性差和成本高的问题,开发性能优良的聚合物PEM显得很有必要. 本文讨论了近年来聚合物PEM的研究进展,分别从聚合物的主链、支链和交联结构角度介绍了分子结构对薄膜相分离、质子导电性、稳定性和电池性能等性能的影响,并讨论了聚合物分子结构设计方面存在的问题,最后对燃料电池用聚合物PEM在未来的发展方向进行了展望.  相似文献   
1000.
Single‐ligand‐based electronically conductive porous coordination polymers/metal–organic frameworks (EC‐PCPs/MOFs) fail to meet the requirements of numerous electronic applications owing to their limited tunability in terms of both conductivity and topology. In this study, a new 2D π‐conjugated EC‐MOF containing copper units with mixed trigonal ligands was developed: Cu3(HHTP)(THQ) (HHTP=2,3,6,7,10,11‐hexahydrotriphenylene, THQ=tetrahydroxy‐1,4‐quinone). The modulated conductivity (σ≈2.53×10?5 S cm?1 with an activation energy of 0.30 eV) and high porosity (ca. 441.2 m2 g?1) of the Cu3(HHTP)(THQ) semiconductive nanowires provided an appropriate resistance baseline and highly accessible areas for the development of an excellent chemiresistive gas sensor.  相似文献   
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